Liquid-level indicating apparatus



Nov. 2 1926.

H. D. BLAKE LIQUID LEVEL INDICATING AEPARATUS Filed Oct. 24, 1922 raranr WILD DJTIi, 01" @LEVELAM), iliHlZQ, Aflrll-CQNQR Gil T GEORGE 3.

FITTE, 62F GILEVELMEJ, UHIO.

Application filed Gotcha! EA, 19222. Serial Ho. 596,641

' The present invention relates to apparatus for indicating liquid levels in liquld holders or other containers, for example, the fuel tanks of motor vehicles.

One object of the invention is to provide an improved level indicating apparatus capahle of accurately indicating at all times the level of the liquid in a tank or holder.

Another object of the invention is'to provide, in an apparatus having a static p cssure system, for indicating liquid levels in a holder, means for supplying air to the system, to replace that which may be oh sorbed by the liquid in the holder or be lost m by change in temperature within the system or leakage.

' Another object of the invention is to provide in a static liquid level indicatin ap-- paratus, means for maintaining a su lcient hi) volume of air in the trap of the apparatus,

whereby the indicating column will accurately show the rise or fall of the level of the li uid contained in the liquid holder.

A. urther object of the invention is to N provide a liquid level indicating apparatus in the form of a container or trap, which communicates at its upper end with a hydrostatic r'essure gage and at its lower end with the interior of the holder to receive 80 pressure therefrom proportionate to the hei ht of the liquid column in the holder.

ther objects of the invention will be apparent tothose skilled in the art to which my invention relates from the following de- 5 scription taken in connection with the accompanying drawing. I

In the drawings, Fig. l is a perspective view of a portion of a vehicle and a fuel feeding system of the vacuum type showing an apparatus embodying my invention applied thereto.

Fig. 2 ice side elevation, partly in section and partly ding amniotic, of the fuel tank and the indicating apparatus. t5 Fig13 is a face view of the gage indicator or scale.

Fig. 4 is a vertical section through the cap for the fuel tank or holder.

Referring to the drawing, 10 designates, 5 conventionally, the body of a motor vehicle having the usual internal combustion engine 11 provided with a carburetor 12, which is conncctcd'thercto by a manifold 13. A vacuum iced tank 14 is arranged above and connected in the usual manner by a pipe 12 to the carburetor l2 and through a pipe 33 wi the manifold 13. The vacuum feed la has a pipe i6, which is carried upon the body 10, and leads to a suitable fuel l tank or holder 17, the pipe 16 extending on through and downwardly into the fuel tank 17., preferably terminating near the bottom thereof.

' Mounted upon the instrument board, vehicle dash or other suitable location upon as the body 10 is a hydrostatic gage 18 (best shown at the top of Fig. 2), preferably comprising a suhstantiall thshaped body having a long arm. 18' of relatively small diameter and a short arm 19 of relatively large diameter. The arms 18, 19, of the U- shaped body 18 are preferably connected by a tube the inner diameter of which is relatively small to retard rapid flow of the liquid from one arm to the other, due to 76- bodily movements of the' vehicle. A body of liquid 20 is placed in this ll-shaped memher 18 and, to retard evaporation, it may be protected at its surface-levels in the arms 18 and 19 by a surface layer of oil or other relatively non-volatile liquid. The long arm 18' is open to the atmosphere at its top, while the shorter arm 19 is-connected at its upper end to one end of a pipe or tube 22 which extends tothe top of the fuel tank 17 and into or through an opening 22 iormedin a cap 23 secured in and removably closing an opening 23"iormed on the top of the tank. The cap 23 carries a depending pipe or tube 24 which communil0 cates with the tube 22 and forms a continuationof the latter. The pipe 24: is-prefer ably of relatively la ge' diameter for the purpose of insuring d" ainage of i'uel therefrom due to it being splashed into the pipe or tube.

The arm 18' of hydrostatic. gage 18 is as sociated with a, plate 18 carrying suitable graduations, constituting a scale whereby variations in. the height of the liquid in'the arm or. column '18 can be easily read and. determined. l I

25 indicams a container connected with the lower-end of the pipe 24, communicating with the interior of the holder 17 and arranged to trap air, whereby the pressure or head of a column of fuel in the holder 17 may be communicated through the pipes 24 and 22 to act on the liquid in the arm or leg 19 of the agelS. The'trap 25 is in the form of a rolativcl J small scaled tank, compartment or container, preferably compris mg a cylindrical body closed at its oppos te owls. The trap is preferably of sue-l1 5 12; that it, as well as the pipe 24 or other game (to which reference will later be made), may loo )ositioned in file holder 17 and removed t erefrom, at will, through the open- 23, for which Impose the ipe 24; may

lac cigidly ooimoc m m fiche cap 23. As shown in the present inmmce the. trap .25 is laced directly in the fuel wider, preffera rly at 4311c lowest oimt therein, but it may be otherwise suita )ly located for the yorposc of accomplishing the rcsulls of this invention. The trap 25 communicates at its lower and with olxo interior of the fuel holder 1? groiersbly by :1 pipe or tuba which may be o'l relatively small diameter. 1

The pipes 16 and 26 are prcfcmlsly in communication Willi cash other: for purposes to be later set forth. In carrying out lfilllfi preferre i formpf mnstmmtion, the pipe 9.6 18 provnle with an up'tumccl free end which cmenfls into the open and of the incl lliochmrg'c pipe 2%, thio arrangement being particularly mlvozrzageous whom: the fuel is {oil in tin; carburetor 12 from a. vacuum tank 14% by a vacuum food meow, for reasons which will lam: be set fiorllb. The pipe 9.6 is of such oize that it will leave ample space around it for the fuel to pass into tho pipe 16,. 26' indicalcs an opening foamed in the pipe 26 at a point bctwccn the lamp 2a ancl connection with the pipc 1% Tile opeoiilg 26 serves to permit the was sure or head of fuel in the holder ll' E0 be transmitted thmugh it to the limp 25 to compress the air in the lotbcr.

if desired; the opening 26 may he omit:- llctl, in "which event the pressure or head of liquid "will o0 communicated through the outer end of the pi e 2%; to #:he imp The opening 26 @2150 serves a. mpplcmental inlet to permit the loci to enter: tho pipe 26 and flow to and through tho pipe For tlacnpurposc of maintaining tho neccssary volume of air in the tray 25 and he tubes 24 and the imp is pFOVHlBLl wiih am gzir supply pipe 21'. The outer end of the pipe 27 communicates with tho atmosphere; its; opposite onci is connectc to the trap 25, and armngefl o0 tlmlz its open free (Will is disposccl in the lower portion lllQil'iOf. Where the trap 25 is an angfiil in the holder 17, the pipe 27 may rise through the fuel holder 1'! to ihe cap 23 10 receive air then izhrou ii. For this JXH'POSQ, the cap (sec 4 has a tilroadiacl opening '28 m its mp, which regiaters with the pipe 27. The ofiwning 28 is closed by a screw plug 29, or t o lilge, rovidccl with openingcfif) throw. in wluchl 811 may pass to the pipe 2?. y preference, a screen 27" may be provided in the. openi'l'igi 28. Tim pipe 27 may llf: aigi ll connected to the cap 23 in any (loszrwl manner so to be rmnrr-sml thorcwith.

The: purp mte of lhc pipc f2? to supply air to the trap 23 0 lllilt any air be absorbed by tho fuel or otherwise be loot from the system, will in: rcplslcml by an? supplied through the pipe 27. "Vlmro my improved indicating apparatus is associated with a fuel holder, from which the fuel i=-' caused to be discharged by a. vacuum or vacuum operating appm'umsklm suction offec'l. incident to each ogm'utlon thereof, Will not only {lmvv the unpaired amount of fucl to the vacuum feed tank 14, but will also create a. pressure in the trap 25 slightly below one atmosphere. As a result of this re duced pressure, air will be drawn into the trap 25 through the i 1pc 527 and replace that;

which has or may have been absorbed by the liquidor otherwise lost, thus resetting the syslcm so that it will again accurately indicute the height of the liouid in the holder 17. The reduced pressure t us created in each operation of; the vacuum operating momma will cause the liquid in the leg 18 to drop but. upon the completion of the vacuum fecal operation, the imdicatln column in the leg 13 will rise therein an; accurately indicoto lhc iici hl: of the liquid then remaining in we E0138? 1?.

From the foregoing dcscriplion, it "will ll: scan filial (1) the reassure system is re-set cach limo fuel is clivered to the vacuum 'fccri 14% without creating an. undesirable Suction or; the gag- 3 l8 and jzhc trap 25 will be automatically refilled with the correct amount of air required to effect an accurate reading on the scale 18.

From the foregoing lescription it will be seen that my invention (1) may be used in imlicalte liquid; levels in tanks or holders of various kinds, and (2) lends itself aclmirabiy for 'me in cox mction with holders from which the liquid is discharged; by vacuum feed: apparatus, since the vacuum effeict serves 2o air into the trap lhroug i me air supply pipe and thus automatically main tame the latter or the pressure system fillcil with the proper or required amount of air to insure its accurate operation in izmnsmiting the qlress'ugc to the gage.

It Will 8 understood that the PR'ESSElT-E s- 5cm may he associal'ed with any other 15 of pi'essui'c gages than filial; disclosed, herein.

Where a. vacuum feecl is proviclcd, I prcfsz' to connect the intake ipe 26 at some suitable point with film supp y 16, for o3 shown and dcscrioeil herein, since in such m'i'angcmcnt a m of the motion of the eng'inc will 2 firm smiitezl direct to the flap 25 and through it to tho pipe 27. This arrangement insures a. suiilicicnfs supply-oi air to or the required volume of air in the trap 25 and mamtaino the premium myofiem which may in proper operating condition to insure accurate indications on the column 18'.

It is obvious that various changes and modifications may be made in the details of .construction and design of the above described embodiment of my invention without departing from the spirit thereof, such chan es and mpdifications being restricted only hy the scope of the appended claim.

What I claim is:

In apparatus of the class described, the combination with a liquid holder, a fuel withdrawing conduit leading from adjacent the bottom of said holder, means to inter mittently withdraw feul from said holder through said conduit, an air trap, an air supply pipe connecting the lower part-of said trap with the atmosphere above said holder, a pressure res onsive gauge, a gauge pipe connecting sai gauge with the upper part of said trap, and a suction pipe having an orifice therein of substantially less area than i the cross-section of the suction pipe, said suction pipe communicating with said air trapand extending, into said conduit and affording free passage around itself and within the conduit for the fuel, whereby the],

withdrawal movement of fuel at intervals in said conduit will cause an entrainment of the contents of the suction pipe and a delivery.

of air through said air supply pipe into said trap to maintain a proper volume of air in said gauge and gauge pipe for accurate indications by said gauge during the intervals between such intermittent movement of fuel; I

In testimony whereof, I have hereunto subscribed my name.

HAROLD D, BLAKE. 

